By Sid Perkins
A sprawling network of seismometers that covers the Los Angeles area could be adapted to provide warning of damaging ground motions from earthquakes in the seconds before those seismic vibes arrive, according to a new analysis.
Some other quake-prone regions already have early-warning systems. For example, seismic instruments about 300 kilometers southwest of Mexico City detect the vibrations spreading from large temblors that occur even farther to the southwest.
That gives residents in the metropolitan area about 70 seconds’ warning.
Could an alert system work in cities, such as Los Angeles, that rest right on top of active fault zones? Most parts of even those at-risk areas could receive a few seconds’ warning, says Richard M. Allen, a seismologist at the University of Wisconsin–Madison.